title: Effects of krill oil containing n-3 polyunsaturated fatty acids in phospholipid form on human brain function: a randomized controlled trial in healthy elderly volunteers.
abstract: BACKGROUND
  Krill oil, rich in n-3 (omega-3) polyunsaturated fatty acids (PUFAs) incorporated in phosphatidylcholine, has been reported to have many effects on physiological function. However, there are few studies using psychophysiological methods published that describe the effects of krill oil on brain function. We investigated the influence of ingestion of krill oil on cognitive function in elderly subjects by using near-infrared spectroscopy and electroencephalography.
  
  
  METHODS
  A randomized, double-blind, parallel-group comparative study design was adopted. Forty-five healthy elderly males aged 61-72 years were assigned to receive 12 weeks of treatment with: medium-chain triglycerides as placebo; krill oil, which is rich in n-3 PUFAs incorporated in phosphatidylcholine; or sardine oil, which is abundant in n-3 PUFAs incorporated in triglycerides. Changes in oxyhemoglobin concentrations in the cerebral cortex during memory and calculation tasks were measured. The P300 component of event-related potentials was also measured during a working memory task.
  
  
  RESULTS
  During the working memory task, changes in oxyhemoglobin concentrations in the krill oil and sardine oil groups were significantly greater than those in the medium-chain triglyceride group at week 12. The differential value for P300 latency in the krill oil group was significantly lower than that in the medium-chain triglyceride group at week 12. With regard to the calculation task, changes in oxyhemoglobin concentrations in the krill oil group were significantly greater than those in the medium-chain triglyceride group at week 12.
  
  
  CONCLUSIONS
  This study provides evidence that n-3 PUFAs activate cognitive function in the elderly. This is especially the case with krill oil, in which the majority of n-3 PUFAs are incorporated into phosphatidylcholine, causing it to be more effective than sardine oil, in which n-3 PUFAs are present as triglycerides.
authors.affiliation: Department of Food and Nutrition, Japan Women's University, Bunkyo-ku, Tokyo, Japan ; Department of Neuropsychiatry, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: Chizuru
authors.initials: C
authors.lastname: Konagai
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yanagimoto
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Hayamizu
authors.forename: Li
authors.initials: L
authors.lastname: Han
authors.forename: Tomoko
authors.initials: T
authors.lastname: Tsuji
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Koga
mesh_terms: D000368:Aged; D000818:Animals; D001921:Brain / Q000187:drug effects*; D019587:Dietary Supplements; D004311:Double-Blind Method; D033201:Euphausiacea; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005399:Fishes; D006801:Humans; D007564:Japan; D008297:Male; D008568:Memory / Q000187:drug effects*; D008875:Middle Aged; D010108:Oxyhemoglobins / Q000032:analysis; D012758:Shellfish
chemical_list: D015525:Fatty Acids, Omega-3; D010108:Oxyhemoglobins
keywords: docosahexaenoic acid; dorsolateral prefrontal cortex; eicosapentaenoic acid; event-related potential; near-infrared spectroscopy; phosphatidylcholine